Chain drive control for scraper bowls



y 7, 1931- v w. J. ADAMS 1,813,011

CHAIN DRIVE CONTROL FOR SCRAPER BOWLS Filed Sept. 28, 1928 I il 4 INVENTOR W e]. Adarn BY @M wm ATTORNEY Patented July 7, 1931 UNITED STATES PATENT OFFICE WILLIAM J. ADAMS OI SANTA. CRUZ, CALIFORNIA, ASSIGNOR TO BALL WAGON GRADER COMPANY, OF STOCKTON, CALIFORNIA, A CORPORATION CHAIN DRIVE CONTROL FOR SCRAPEB BOWLS Application filed September 28, 1928. Serial No. 308,995.

This invention relates to devices for controlling the raising and lowering of scraper bowls and particularly represents improvements over the control structure for this purpose shown. in the patent to Charles E. and Samuel H. Ball, No. 1,593,007, dated July 20, 1926. a

The control structure consists essentially of a sheave connected in drivin relation with a ground engaging wheel 0% porting frame of the scraper, a sprocket wheel, an endless chain aboutthe sprocket and sheave, a hand controlled idler sheave for tightening the chain so that it will fric-' tionally engage the other sheave and cause the sprocket to be rotated, and operating connections between the sprocket and the scraper bowl to cause the latter to be raised when the sprocket is thus rotated. This provides very smooth 0 erating mechanism for controlling the raising and lowering of the bowl and was much cheaper than a disc clutch or a similar mechanism. In the prevlous devlce however, the cha-1nwasof the ordinary roller type having the usual narrow side plates on the links, and as a result these plates soon cut grooves in the sheave unduly wearing same, and themselves wearing out very quickly so that frequent.

link replacements were necessary.

Also the small area of contact of the chain link plates with the sheave necessitates a very heavy pressure being placed on the idler to, obtain the desired working engagement of the chain with the sheave. The principal object of the present invention is to avoidthese objectionable and defective features by constructing the chain so that the sheavewill not become grooved and the chain links willnot wear out so fast, and less pressure on the control idler is necessary to obtain the proper non-slipping adhesion of the chain on the sheave.

A further object of the invention is to produce a simple and inexpensive device and yet one which will be exceedingly effective for the purpose for which it is designed.

the sup- 4 parts as will fully appear by a perusal of the following specification and claims.

In the drawings similar characters of reference indicate corresponding parts in the several views: Fig. 1 is a side elevation of a portion of a scraper structure equipped with my improved chain control device, the near wheel being removed.

Fig. 2 is an enlarged fragmentary section of the special chain and sprocket wheel.

Fig. 3 is a similar view of the chain and sheave.

Fig. 4 is a fragmentary plan view of the chain.

Referring now more particularly to the characters of reference on the drawings, the numeral 1 denotes the main side frames of the scraper, which support a transverse axle 2 adjacent its rear end, on which the ground engaging wheels 3 -and a large grooved sheave 4 are mounted in common driving relation. The scraper bowl 5 is suspended between the frames 1 by links 6 and is raised by cable elements 7 passing from the bowl over sheaves 8 to a drum 9 mounted on a transverse shaft 10 disposed above the axle 2. It is here to be noted that the shape and mounting of the bowl, and the particular form of connection between the bowl and the shaft 10 may be varied considerably, since they form no part of the present inventionand are merely shown for purposes of illustration.-

Fixed on the shaft 10 is a sprocket wheel 11 having teeth 12 spaced to engage only alternate links 13 of the chain which passes about the sprocket wheel and the sheave 4..

The intermediate links 14 of the chain have solid web plates 15 extending across the space between the side plates of said links the side plates of the links 13 as shown in Fig. 3, so that such plates will not engage and cut into the sheave.

These intermediate links are preferably the widest ones of the chain, so that the area of the web plates is as great as possible without extending them beyond the sides. of the link plates.

the chain plates 15 in frictional driving relation with the sheave when desired, in order to cause the sprocket wheel to be rotated,

an idler sheave 19 is mounted on one end of a hand controlled lever 20, pivoted intermediate its ends on the frame 1, said idler being positioned to engage the outer face of the chain intermediate the sprocket and sheave, as in said aforementioned patent. While I have here shown and described this arrangement as being particularly intended to control the movement of a scraper bowl, it will be obvious that its use is not limited to this purpose, since it can be employed to control the rotation of the sprocket wheel for any purpose desired.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims. m

Having thus described my invention what I claim as new and useful and desire to secure by Letters Patent is:

1. In combination, a sheave, a sprocket wheel, an endless chain about the sprocket and sheave, the teethof the wheel engaging only alternate links of the chain, and cross plates on the intermediate links to engage the face of the sheave throughout their area and projecting from the sheave engaging sides of the links to maintain said alternate links clear'of the sheave.

2. In combination, a sheave, a sprocket wheel mediate links and extending laterally thereof to engage the face of the sheave; said plates being curved on. an are equal to that an endless chain about the sprocket and sheave, and plates fixed on the inter-- 3. A chain for use about a sprocket wheel comprising links having side plates, and

webs extending between the side plates of alternate links, said webs projecting outwardly of the adjacent edges of the Side plates ofthe intermediate links from the same side of the chain as that adapted to lie against the wheel.

4. A structure as in claim 1 in which the sprocket wheel, at the base of the teeth, is recessed to receive the plates in clearance relation when said plates are passing about the wheel.

In testimony whereof I aflEix my signature. WILLIAM J. ADAMS. 

